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Governor Details.


flat cheeks lined out These being shaped, the boss is next
marked oif and milled, and the hole drilled, the slot taken out as
in previous cases, finishing by hand. The key for the mitre
wheel is finally grooved with a milling cutter, The Sleeve B,
being cast solid, is first centred, and the thickness of the bosses
lined. It is drilled in the lathe, and then slipped over a
mandrel to turn, and to screw the end. The flat surfaces of the
bosses are next shaped across, and the space between taken out
with a tool of the exact width, The holes are marked off and
drilled, and the bosses filed round, after which the sleeve is fitted
to the arms c by chipping out the socket with cross-cut chisel
and finishing with a curved file much used by brass finishers,
called a 'riffler' (see Q, Fig. 262). Mark out key-way for the
weight E, and cut the same by hand.

The Nut for the sleeve is bored and screwed in a chuck, and
turned on a mandrel, and the octagon milled by fixing on a
dividing circle. Drill and tap for the side screw, but only file
out the corresponding slot in the sleeve after M is put into place,
and the nut advanced to give the requisite tightness, The
Lower Arm c is packed up as at H, Fig. 262, and the fork
bridged; then the centre and the flat cheeks are lined, the fork
centres struck, the lengths marked off, and the centres of the
bosses squared up. Next turn the shank, and slot or mill the
fork to the marked lines. Lay the arm in the position j, and
after scribing the centre line, strike the curves of the bosses and
pin-holes, and scribe the width of the fork. Shape and mill to
the lines, and drill the holes. The Radius Arm D is centred
and lined as at K, Fig. 262, and the shoulder line marked off, as
well as the commencement of the small curve to ball Set in the
lathe, and turn down the shank. Then prepare a template for
the ball, as shewn at L, Fig. 262. First turn to diameter as a
cylinder, and surface the end to length; then feed at 458, as at^
Fig. 262 j continue to halve these angular feeds until the ball
is approximately spherical, as tried with template, and finish with
a keen hand tool ground to the ball curvature. Mark the centre
of the ball while revolving in the lathe, and set on marking-
table to get the cross centre, as at M, Fig. 262. The boss is then
finished as usual, and the hole drilled through the ball The